is there Haskellmagic that I still need to learn?
one bit of magic, coming right up!-) of course, we haskellers are the lazy types, and if none of that helps, some Monad often does. in ghci or hugs, try ':browse Data.Maybe' and ':info Maybe'. in particular, 'case . of Nothing -> . ; Just . -> .' calls for 'maybe', and nested chains of such cases call for 'Monad Maybe' and, possibly, 'MonadPlus Maybe' (the latter from 'Control.Monad'). consider these two (try unfolding the definitions, and compare with your code): maybe (error "nothing") id (lookup False []) do { it <- lookup False []; return it }`mplus` return 42 hmm. now, how do i point to the source for that? anyway, here it is: instance Monad Maybe where (Just x) >>= k = k x Nothing >>= k = Nothing return = Just fail s = Nothing instance MonadPlus Maybe where mzero = Nothing Nothing `mplus` ys = ys xs `mplus` ys = xs hth, claus